ACPICA: Utilities: Add _CLS processing

ACPICA commit 9a2b638acb3a7215209432e070c6bd0312374229

ACPI Device object often contains a _CLS object to supply PCI-defined class
code for the device. This patch introduces logic to process the _CLS
object. Suravee Suthikulpanit, Lv Zheng.

Link: https://github.com/acpica/acpica/commit/9a2b638a
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

5 files changed, 148 insertions, 4 deletions

diff --git a/drivers/acpi/acpica/acinterp.h b/drivers/acpi/acpica/acinterp.h
index 1886bde54b5d..7ac98000b46b 100644
--- a/drivers/acpi/acpica/acinterp.h
+++ b/drivers/acpi/acpica/acinterp.h
@@ -468,6 +468,8 @@ void acpi_ex_eisa_id_to_string(char *dest, u64 compressed_id);
 
 void acpi_ex_integer_to_string(char *dest, u64 value);
 
+void acpi_ex_pci_cls_to_string(char *dest, u8 class_code[3]);
+
 u8 acpi_is_valid_space_id(u8 space_id);
 
 /*
diff --git a/drivers/acpi/acpica/acutils.h b/drivers/acpi/acpica/acutils.h
index d49f5c7a20d9..6391c9706e84 100644
--- a/drivers/acpi/acpica/acutils.h
+++ b/drivers/acpi/acpica/acutils.h
@@ -430,6 +430,10 @@ acpi_status
 acpi_ut_execute_CID(struct acpi_namespace_node *device_node,
 		    struct acpi_pnp_device_id_list ** return_cid_list);
 
+acpi_status
+acpi_ut_execute_CLS(struct acpi_namespace_node *device_node,
+		    struct acpi_pnp_device_id **return_id);
+
 /*
  * utlock - reader/writer locks
  */
diff --git a/drivers/acpi/acpica/exutils.c b/drivers/acpi/acpica/exutils.c
index 3f4225e95d93..30c3f464fda5 100644
--- a/drivers/acpi/acpica/exutils.c
+++ b/drivers/acpi/acpica/exutils.c
@@ -380,6 +380,38 @@ void acpi_ex_integer_to_string(char *out_string, u64 value)
 
 /*******************************************************************************
  *
+ * FUNCTION:    acpi_ex_pci_cls_to_string
+ *
+ * PARAMETERS:  out_string      - Where to put the converted string (7 bytes)
+ * PARAMETERS:  class_code      - PCI class code to be converted (3 bytes)
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Convert 3-bytes PCI class code to string representation.
+ *              Return buffer must be large enough to hold the string. The
+ *              string returned is always exactly of length
+ *              ACPI_PCICLS_STRING_SIZE (includes null terminator).
+ *
+ ******************************************************************************/
+
+void acpi_ex_pci_cls_to_string(char *out_string, u8 class_code[3])
+{
+
+	ACPI_FUNCTION_ENTRY();
+
+	/* All 3 bytes are hexadecimal */
+
+	out_string[0] = acpi_ut_hex_to_ascii_char((u64)class_code[0], 4);
+	out_string[1] = acpi_ut_hex_to_ascii_char((u64)class_code[0], 0);
+	out_string[2] = acpi_ut_hex_to_ascii_char((u64)class_code[1], 4);
+	out_string[3] = acpi_ut_hex_to_ascii_char((u64)class_code[1], 0);
+	out_string[4] = acpi_ut_hex_to_ascii_char((u64)class_code[2], 4);
+	out_string[5] = acpi_ut_hex_to_ascii_char((u64)class_code[2], 0);
+	out_string[6] = 0;
+}
+
+/*******************************************************************************
+ *
  * FUNCTION:    acpi_is_valid_space_id
  *
  * PARAMETERS:  space_id            - ID to be validated
diff --git a/drivers/acpi/acpica/nsxfname.c b/drivers/acpi/acpica/nsxfname.c
index d66c326485d8..dc0836a9cf17 100644
--- a/drivers/acpi/acpica/nsxfname.c
+++ b/drivers/acpi/acpica/nsxfname.c
@@ -260,7 +260,7 @@ static char *acpi_ns_copy_device_id(struct acpi_pnp_device_id *dest,
  *              control methods (Such as in the case of a device.)
  *
  * For Device and Processor objects, run the Device _HID, _UID, _CID, _SUB,
- * _STA, _ADR, _sx_w, and _sx_d methods.
+ * _CLS, _STA, _ADR, _sx_w, and _sx_d methods.
  *
  * Note: Allocates the return buffer, must be freed by the caller.
  *
@@ -276,11 +276,12 @@ acpi_get_object_info(acpi_handle handle,
 	struct acpi_pnp_device_id *hid = NULL;
 	struct acpi_pnp_device_id *uid = NULL;
 	struct acpi_pnp_device_id *sub = NULL;
+	struct acpi_pnp_device_id *cls = NULL;
 	char *next_id_string;
 	acpi_object_type type;
 	acpi_name name;
 	u8 param_count = 0;
-	u8 valid = 0;
+	u16 valid = 0;
 	u32 info_size;
 	u32 i;
 	acpi_status status;
@@ -320,7 +321,7 @@ acpi_get_object_info(acpi_handle handle,
 	if ((type == ACPI_TYPE_DEVICE) || (type == ACPI_TYPE_PROCESSOR)) {
 		/*
 		 * Get extra info for ACPI Device/Processor objects only:
-		 * Run the Device _HID, _UID, _SUB, and _CID methods.
+		 * Run the Device _HID, _UID, _SUB, _CID, and _CLS methods.
 		 *
 		 * Note: none of these methods are required, so they may or may
 		 * not be present for this device. The Info->Valid bitfield is used
@@ -363,6 +364,14 @@ acpi_get_object_info(acpi_handle handle,
 			     sizeof(struct acpi_pnp_device_id_list));
 			valid |= ACPI_VALID_CID;
 		}
+
+		/* Execute the Device._CLS method */
+
+		status = acpi_ut_execute_CLS(node, &cls);
+		if (ACPI_SUCCESS(status)) {
+			info_size += cls->length;
+			valid |= ACPI_VALID_CLS;
+		}
 	}
 
 	/*
@@ -486,6 +495,11 @@ acpi_get_object_info(acpi_handle handle,
 		}
 	}
 
+	if (cls) {
+		next_id_string = acpi_ns_copy_device_id(&info->class_code,
+							cls, next_id_string);
+	}
+
 	/* Copy the fixed-length data */
 
 	info->info_size = info_size;
@@ -510,6 +524,9 @@ cleanup:
 	if (cid_list) {
 		ACPI_FREE(cid_list);
 	}
+	if (cls) {
+		ACPI_FREE(cls);
+	}
 	return (status);
 }
 
diff --git a/drivers/acpi/acpica/utids.c b/drivers/acpi/acpica/utids.c
index 27431cfc1c44..3afe07f19b9f 100644
--- a/drivers/acpi/acpica/utids.c
+++ b/drivers/acpi/acpica/utids.c
@@ -1,6 +1,6 @@
 /******************************************************************************
  *
- * Module Name: utids - support for device Ids - HID, UID, CID
+ * Module Name: utids - support for device Ids - HID, UID, CID, SUB, CLS
  *
  *****************************************************************************/
 
@@ -416,3 +416,92 @@ cleanup:
 	acpi_ut_remove_reference(obj_desc);
 	return_ACPI_STATUS(status);
 }
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ut_execute_CLS
+ *
+ * PARAMETERS:  device_node         - Node for the device
+ *              return_id           - Where the _CLS is returned
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Executes the _CLS control method that returns PCI-defined
+ *              class code of the device. The _CLS value is always a package
+ *              containing PCI class information as a list of integers.
+ *              The returned string has format "BBSSPP", where:
+ *                BB = Base-class code
+ *                SS = Sub-class code
+ *                PP = Programming Interface code
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ut_execute_CLS(struct acpi_namespace_node *device_node,
+		    struct acpi_pnp_device_id **return_id)
+{
+	union acpi_operand_object *obj_desc;
+	union acpi_operand_object **cls_objects;
+	u32 count;
+	struct acpi_pnp_device_id *cls;
+	u32 length;
+	acpi_status status;
+	u8 class_code[3] = { 0, 0, 0 };
+
+	ACPI_FUNCTION_TRACE(ut_execute_CLS);
+
+	status = acpi_ut_evaluate_object(device_node, METHOD_NAME__CLS,
+					 ACPI_BTYPE_PACKAGE, &obj_desc);
+	if (ACPI_FAILURE(status)) {
+		return_ACPI_STATUS(status);
+	}
+
+	/* Get the size of the String to be returned, includes null terminator */
+
+	length = ACPI_PCICLS_STRING_SIZE;
+	cls_objects = obj_desc->package.elements;
+	count = obj_desc->package.count;
+
+	if (obj_desc->common.type == ACPI_TYPE_PACKAGE) {
+		if (count > 0
+		    && cls_objects[0]->common.type == ACPI_TYPE_INTEGER) {
+			class_code[0] = (u8)cls_objects[0]->integer.value;
+		}
+		if (count > 1
+		    && cls_objects[1]->common.type == ACPI_TYPE_INTEGER) {
+			class_code[1] = (u8)cls_objects[1]->integer.value;
+		}
+		if (count > 2
+		    && cls_objects[2]->common.type == ACPI_TYPE_INTEGER) {
+			class_code[2] = (u8)cls_objects[2]->integer.value;
+		}
+	}
+
+	/* Allocate a buffer for the CLS */
+
+	cls =
+	    ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_pnp_device_id) +
+				 (acpi_size) length);
+	if (!cls) {
+		status = AE_NO_MEMORY;
+		goto cleanup;
+	}
+
+	/* Area for the string starts after PNP_DEVICE_ID struct */
+
+	cls->string =
+	    ACPI_ADD_PTR(char, cls, sizeof(struct acpi_pnp_device_id));
+
+	/* Simply copy existing string */
+
+	acpi_ex_pci_cls_to_string(cls->string, class_code);
+	cls->length = length;
+	*return_id = cls;
+
+cleanup:
+
+	/* On exit, we must delete the return object */
+
+	acpi_ut_remove_reference(obj_desc);
+	return_ACPI_STATUS(status);
+}